Problem: Jessica ate 1 slice of cake. Michael ate 1 slice. If there were initially 3 slices, what fraction of the cake is remaining?
Explanation: $\text{fraction of cake eaten} = \dfrac{\text{number of slices remaining}}{\text{number of slices total}}$ Together they ate 2 slices, which leaves 1 out of 3 slices remaining. There is $\dfrac{1}{3}$ of the cake remaining.